Passenger Side Airbag

ABSTRACT

An airbag includes at least one panel defining an interior of the airbag, a divider positioned in the interior so as to divide the interior into an upper chamber and a lower chamber, and at least one tethering mechanism positioned within the lower chamber. The at least one tether mechanism is structured and attached to the at least one panel so as to restrict movement of a portion of the at least one panel during airbag inflation such that a first recess is formed along an exterior surface of the airbag when the airbag is inflated.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application Ser.No. 61/929,764, filed on Jan. 21, 2014, the disclosure of which isincorporated herein by reference in its entirety.

BACKGROUND OF THE INVENTION

The present invention relates to a passenger side airbag, which isfilled with gas during an emergency situation such as, for example, afrontal or side impact. It will be appreciated that the structuralbenefits and design principles may of course be extended to airbagstypically employed in other areas of the vehicle, such as a side airbag,for example.

Current airbag cushion designs may include multiple chambers and mayincorporate an inter-chamber valving system that allows gas to flow fromone chamber to another. These cushions are configured to rapidly contacta vehicle occupant when inflated, to limit movement of the passengerhead, neck and thoracic regions. However, these cushion designs do notdifferentiate between these different regions with regard to thestiffness or resistance of the various portions of the airbag to contactwith each region.

Research has shown that the masses of the various body portionscontacting an airbag differ greatly. For example, the mass ratio of theThorax to Head & Neck regions may range from between 5:1 to 8:1,depending on the sex of the individual. Due to the differences in bodypart masses and the dynamics of contact between the occupant and thecushion, it has proven difficult to design a multi-chamber airbag whichprovides optimum protection for each portion of the body contacting theairbag.

Thus, a need exists for an airbag design which permits the stiffness orresistance to occupant impact provided by each portion of the airbag tobe adjusted according to the time elapsed since the initiation of airbagdeployment, the size of the occupant, and/or the masses of differentportions of the occupant's body contacting an associated portion of theairbag. A need also exists for an airbag structure adaptable forcontrolling a neck extension moment (defined as an undesirable rotationof the head and neck about the torso at the neck-torso junction)resulting from contact of the passenger with the airbag.

SUMMARY OF THE INVENTION

In one aspect of the embodiments described herein, an airbag isprovided. The airbag includes at least one panel defining an interior ofthe airbag, a divider positioned in the interior so as to divide theinterior into an upper chamber and a lower chamber, and at least onetethering mechanism positioned within the lower chamber. The at leastone tether mechanism is structured and attached to the at least onepanel so as to restrict movement of a portion of the at least one panelduring airbag inflation such that a first recess is formed along anexterior surface of the airbag when the airbag is inflated.

In another aspect of the embodiments of the described herein, an airbagis provided. The airbag includes at least one panel defining an interiorof the airbag, a divider positioned in the interior so as to divide theinterior into an upper chamber and a lower chamber, and at least onetether positioned within the upper chamber. The at least one tether isattached to the divider and to a portion of the at least one panel so asto restrict movement of a portion of the divider in a direction towardthe lower chamber during inflation of the airbag.

In another aspect of the embodiments of the described herein, an airbagis provided. The airbag includes at least one panel defining an interiorof the airbag, and a divider positioned in the interior so as to dividethe interior into an upper chamber and a lower chamber. At least aportion of a leading edge of the divider is not attached to an occupantcontact side of the at least one panel.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side cross-sectional view of a passenger-side airbag (in aninflated state) in accordance with one embodiment described herein.

FIG. 2 is a front view of the airbag of FIG. 1.

FIG. 3 is a schematic perspective cutaway view of the airbag of FIG. 1,showing elements of the airbag interior.

FIG. 4 is a side view of the airbag of FIG. 1 mounted and deployed in avehicle in front of a seated passenger.

FIG. 5 is a perspective view of the passenger-side airbag of FIGS. 1-4,shown in an inflated state and mounted in a vehicle.

FIG. 6 is a perspective view of an airbag in accordance with anotherembodiment described herein, shown in an inflated state and mounted in avehicle.

FIG. 7 is a schematic view showing relative proportions ofAnthropomorphic Test Devices and relevant parameters used to define thedesired positioning of the divider within the airbag, in accordance withembodiments described herein.

FIG. 8 is a side view of a Hybrid III 5th percentile female testAnthropomorphic Test Device contacting a deployed airbag having adivider positioned within the airbag in accordance with an embodimentdescribed herein.

FIG. 9 is a side view of a Hybrid III 50th percentile maleAnthropomorphic Test Device contacting a deployed airbag having adivider positioned within the airbag in accordance with an embodimentdescribed herein.

FIG. 10 is a side view of a vehicle passenger compartment showing aseated Anthropomorphic Test Device prior to deployment of a vehicleairbag.

FIG. 11 is the side view of FIG. 10 just after the airbag has beenactivated and begins to deploy.

FIG. 12 is the side view of FIG. 11 after additional time has elapsedafter airbag activation.

FIG. 13 is the view of FIG. 12 after full contact of the head and neckregions of the passenger with the airbag.

FIG. 14 is the view of FIG. 13 after contact of the thoracic region ofthe passenger with the seam of the leading edge of the airbag dividerpanel.

FIG. 15 is a dividing panel in a cross-sectional plan view of anuninflated airbag showing a location of a representative inter-chambervent in the divider.

FIG. 16 is a side view of a portion of the airbag shown in FIG. 15 in aninflated state, showing a location of the inter-chamber vent, andshowing the initial stage of inflation of one embodiment of the airbagin relation to a head of a Hybrid III 6-Year Old Anthropomorphic TestDevice.

FIG. 16A is cross-sectional side view of the airbag embodiment shown inFIG. 16, in an inflated state.

FIG. 16B is a magnified view of a portion of the cross-sectional sideview shown in FIG. 16A.

FIG. 17 is a side view of the airbag of FIG. 16 showing a later stage ofinflation of the airbag.

FIG. 18 is a schematic view of Position-2 for Out of Position testingfor a Hybrid III 3 and 6-Year Old Anthropomorphic Test Device (ATD).

FIG. 19 shows a schematic representation of gas flow from an upperairbag chamber through a divider opening and into a lower chamber.

FIG. 20 is a perspective view of a portion of an interior of an airbagincorporating one embodiment of a divider and valve mechanism describedherein.

FIG. 21A is a cross-sectional side view of a portion of the airbag shownin FIG. 20 during flow of gases from an upper chamber of the airbag to alower chamber of the airbag.

FIG. 21B is a cross-sectional front view of the portion of the airbagshown in FIG. 21A.

FIG. 22A is a cross-sectional side view of the portion of the airbagshown in FIG. 21A during flow of gases from the lower chamber of theairbag to the upper chamber of the airbag.

FIG. 22B is a cross-sectional front view of the portion of the airbagshown in FIG. 22A.

FIG. 23 illustrates a perspective view of one embodiment of an inventiveenhancement using a unique tethered system, with the tether attached tothe airbag divider and main panel.

FIG. 23A is a cross-sectional perspective view of another embodiment ofan inventive enhancement using a unique tethered system, with the tetherattached to the airbag divider and main panel.

FIG. 24 is a cross-sectional perspective view of another embodiment ofan inventive enhancement using a unique tethered system, with the tetherattached to the airbag divider and main panel.

FIG. 24A is a cross-sectional view of the airbag shown in FIG. 24.

FIG. 25 is a cross-sectional perspective view of another embodiment ofan inventive enhancement using a unique tethered system, with the tetherattached to the airbag divider and main panel.

FIG. 25A is a cross-sectional view of the airbag shown in FIG. 25.

FIG. 25B is a schematic cross-sectional side view of an airbag inaccordance with a particular embodiment described herein.

FIG. 25C is a front or passenger-facing view of the airbag embodimentshown in FIG. 25B.

FIGS. 26A and 26B are schematic cross-sectional side views of an airbagin accordance with an embodiment described herein, showing a portion ofthe airbag interior volume shared by the upper and lower chambers whenthe bag is inflated.

FIG. 27 is a plan cross-sectional view of an airbag incorporating adivider in accordance with an embodiment described herein withalternative valve location along a leading edge of the divider panel.

FIG. 28 is a schematic cross-sectional plan view of a portion of anairbag incorporating a divider with alternative valve locations, inaccordance with another embodiment described herein.

FIG. 29 is a plan view of the divider shown in FIG. 28.

FIG. 30 is a schematic cross-sectional side view of an airbagincorporating an internal tethering mechanism in accordance with anembodiment described herein.

FIG. 31 is a schematic cross-sectional side view of an airbagincorporating an internal tethering mechanism in accordance with anotherembodiment described herein.

FIG. 32 is a front (passenger-facing) view of the airbag embodimentshown in FIG. 33.

FIG. 33 is a cross-sectional side view showing attachment of oneembodiment of an internal tether to occupant contact and rear surfacesof an airbag.

FIG. 33A is a perspective view of one embodiment of a tether mechanismincorporated into the airbag embodiment of FIG. 33.

FIG. 34 is a cross-sectional plan view showing an airbag including oneembodiment of an internal tethering mechanism.

FIG. 35 is a cross-sectional plan view of the airbag embodiment shown inFIGS. 32 and 33.

FIG. 36 is a side cross-sectional perspective view of the airbagembodiment shown in FIG. 33.

FIGS. 37 and 38 are perspective views of the additional airbagembodiments, each incorporating a recess formed in an occupant contactface of the airbag.

FIG. 39 is a schematic side view of the airbag embodiment of FIG. 33 ina deployed condition wrapped over the head of a child ATD.

FIG. 39A is a schematic side view of an airbag in accordance with anembodiment as described herein, configured to cover the head of aninfant positioned in an infant car seat when inflated.

FIG. 40 is a view of a vehicle occupant protection system incorporatingan airbag in accordance with an embodiment of the present invention.

FIG. 41 is a side view of a 3 year-old Anthropomorphic Test Device inpositioned in Position-1 for NHTSA Out of Position testing under FMVSSStandard No. 208, prior to activation of a vehicle airbag.

FIG. 42 is the side view of FIG. 41 after activation of a vehicleairbag.

FIG. 43 is a schematic cross-sectional plan view of a portion of anairbag incorporating a divider and flow restriction valve mechanism inaccordance with another embodiment described herein.

FIG. 44 is a schematic perspective view of the airbag shown in FIG. 43.

FIG. 45 is a schematic cross-sectional plan view of a portion of anairbag incorporating a divider and flow restriction valve mechanism inaccordance with another embodiment described herein.

FIG. 45A is a schematic perspective view of the airbag shown in FIG. 45.

FIG. 46 is a schematic cross-sectional side view of one embodiment of anairbag incorporating a valve mechanism into the leading edge of thedividing panel, showing the valve in an open condition.

FIG. 46A is the side view of FIG. 46 showing the valve in an opencondition.

FIG. 47 is a schematic cross-sectional side view of another embodimentof an airbag incorporating a valve mechanism into the leading edge ofthe dividing panel, showing the valve in an open condition.

FIG. 47A is the side view of FIG. 47 showing the valve in an opencondition.

DETAILED DESCRIPTION

Like reference numerals refer to like parts throughout the descriptionof several views of the drawings. In addition, while target values arerecited for the dimensions of the various features described herein, itis understood that these values may vary slightly due to such factors asmanufacturing tolerances, and also that such variations are within thecontemplated scope of the embodiments described herein.

Embodiments of the present invention will be described below withreference to the drawings. One of ordinary skill in the art willappreciate the various aspects of airbag design, construction andoperation applicable to the embodiments of the present inventiondescribed herein. U.S. Pat. Nos. 6,886,857, 7,857,347, 8,128,124, and8,322,748, for example, describe many such aspects and are incorporatedherein by reference in their entirety, but not by way of limitation.

FIGS. 1-4 are views of a passenger-side airbag 10 (in an inflated state)according to an embodiment of the present invention. The airbagembodiment shown in FIGS. 1-4 is formed from three panels which, incombination, define an outer shell of the airbag. Specifically, theairbag is formed of a main panel 12, a right side (when viewing theairbag from a seated position) panel 14, and a left side panel 16opposite the right side panel 14. Each of the side panels 14, 16 may begenerally planar (when separated from the other panels and laid out on aflat surface). The main panel 12 connects the left and right panels andwraps around the airbag 10. As a result, the entirety of the right edgeof the main panel 12 is connected along a seam 70 (e.g., by stitching,sewing, or other suitable means) to the right panel 14 and the entiretyof the left edge of the main panel 12 is connected along a seam 72(e.g., by stitching, sewing, or other suitable means) to the left panel16.

The main panel 12 has both a front, impact side 20 and a rear, inflationside 22. After wrapping around the airbag 10, ends of the main panel 12are joined at the rear inflation side. In addition, the rear inflationside 22 has slits (not shown) which are sized to receive an inflator(not shown), and may also include holes (not shown) which are sized toreceive bolts (or other suitable fasteners) that are configured tosecure the airbag 10 to the body of an automobile (or other device). The“front side” of the airbag or of main panel 12 is that portion of theairbag structured and positioned so as to be impacted first by a vehicleoccupant when the airbag is activated.

Portions of one or more of panels 12, 14, 16 defining upper chamber 102may incorporate one or more cushion vents 106 therein to release gasfrom the upper chamber to the environment in a controlled manner duringcontact between a passenger and the airbag.

Referring to FIGS. 1-4, a dividing panel or divider 100 is stitched orotherwise suitably attached along a perimeter thereof to interiorsurfaces of the main, left and right panels. The divider 100 is attachedto the panel interior surfaces along a seam 110 so as to form a gas-flowrestricting seal between the divider and the panels to which it isattached. In a particular embodiment, the divider 100 is attached to thepanel interior surfaces along seam 110 so as to form a gas-tight sealbetween the divider and the panels to which it is attached. Divider 100divides the airbag interior into an upper chamber 102 and a lowerchamber 104. The divider is also attached to other portions of theairbag (via stitching, tethers, or any other suitable method or methods)so as to provide a desired profile (for example, as shown in the sideview of FIG. 1) and a desired location of the divider leading edge, asdescribed herein.

In embodiments described herein, the inflated shapes of the airbag 10and divider 100 and the positions of the intersections between divider100 and the interior portions of the panels 12, 14, 16 to which thedivider is attached are configured so as to ensure that the head andneck regions (collectively designated 302 for a Hybrid III 5thpercentile female Anthropomorphic Test Device (ATD) 305, 402 for aHybrid III 50th percentile male test ATD 405, and 502 for a Hybrid III95th percentile male test ATD 505, as shown in FIG. 7) of passengers ofvarious sizes impact the bag along the exterior of the upper chamber 102of the bag (i.e., that the upper chamber 102 absorbs the impact of thehead and neck regions of the passenger). The configuration of thedivider 100, its positioning within the airbag, and the position of theportion 110 a of the seam 110 attaching the divider leading edge 100 ato the panel 12 enable the cushion to match the forward movement of therelatively heavier thoracic regions (generally designated 304 in ATD305, 404 in ATD 405, and 504 in ATD 505) to the forward movement of therelatively smaller and lighter head & neck regions 302, 402, 502. Asknown in the pertinent art, an anthropomorphic test device or ATD is ahuman form in shape, mass and mechanical response, equipped with sensorsincluding accelerometers, deflection sensors and other measurementdevices, to simulate the performance of the human body. It is used inthe assessment of injury potential in crash safety testing.

Referring to FIGS. 1-4, in one example, edge 100 a of divider 100attached to an interior surface of the front side 20 of main panel 12defines a leading edge of the divider 100. Leading edge 100 a isattached to the main panel front side 20 along seam 110 and isconfigured such that the leading edge 100 a and the portion 110 a of theseam 110 attaching the leading edge to the front side will reside belowthe neck and head regions of any passenger contacting the airbag frontside (more specifically, within the zone Z shown in FIG. 7 and definedbelow), when the airbag mounted in the vehicle and is fully inflated. Inthis configuration of the airbag, the passenger head and neck regionswill always contact the airbag along an exterior of the bag upperchamber 102.

In the particular embodiment shown in FIGS. 1-4, divider 100 is attachedto the inner surfaces of the airbag panels 12, 14, 16 so as to form acurved surface 100 b having a downwardly angling portion 100 cterminating in leading edge 100 a connected to front side 20. However,the seams connecting the divider 100 to the main and side panels mayhave any locations and/or configurations necessary to facilitateattachment to the panel 12 at the desired location within zone Z asdescribed herein. For example, FIG. 5 shows the airbag embodiment ofFIGS. 1-4 in an inflated state and mounted in a vehicle.

In particular embodiments described herein, the various airbag elementsare shaped and connected to each other so that, when fully inflated, thefront side 20 of the bag aids in maintaining alignment of the head,neck, and thoracic body regions along a line L as shown in FIG. 4 duringearly occupant interaction with the airbag, wherein the upper bodyportion of the occupant pivots forward from the hip pivot axis 202 alongline L. As the occupant contacts the bag, it is desirable to maintainthe alignment of the head and thorax regions and balance the energyabsorption by the bag from the head and the thorax, to minimize motionor rotation of the head about the neck and with respect to the torso. Asseen in FIG. 4, the bag is structured such that the portions of theupper and lower chambers of the cushion facing the occupant 20 form anessentially flat plane, indicated by the line P in the drawing. At theearly stages of airbag inflation, the occupant seatbelt (not shown)tensions to restrain the occupant's lower thoracic region in the seat.Thus, at this point, the hip pivot axis 202 resides at a first locationH1. At a later stage of inflation, as the seatbelt tensioner relaxes,thereby permitting the pivot axis 202 to shift from location H1 to asecond location H2, closer to or lying on plane P. Thus, during thelater stages of inflation, due to movement of the occupant, the line Lapproaches or lies along plane P.

Referring to FIGS. 6 and 7, in embodiments described herein, the dividerleading edge 100 a is attached to the main panel along a seam 110positioned so as to reside within a zone Z defined at a lower end Z2 bythe hip pivot axis 202 of a seated Hybrid III 5th female ATD 305, and atan upper end Z1 by the shoulder pivot 206′ of a seated Hybrid III 50thMale ATD 405, inclusive. These boundary positions and othercharacteristics of all the test ATD's described herein are specified in49 CFR Part 572, which is incorporated herein by reference in itsentirety, and which may be found, for example, athttp://www.gpo.gov/fdsys/pkg/CFR-2011-title49-vol7/pdf/CFR-2011-title49-vol7-part572.pdf.In a particular embodiment, the hip pivot 202 of the seated Hybrid III5th female ATD resides at a vertical distance of 3.30 inches above theportion of the seat in contact with the ATD, and the shoulder pivot 206′of the seated Hybrid III 50th male ATD resides at a distance of 17.5inches above the portion of the seat in contact with the ATD. Thus, inthe particular embodiment, the dimension of the zone Z is 14.2 inches.

It is noted that the hip pivot axes of the seated ATD's 305, 405, and505 are collinear or at the same level, so that the hip pivot of theseated Hybrid III 50th male ATD 405 may be referred to as 202′ and thehip pivot of the seated Hybrid III 95th male ATD 505 may be referred toas 202″. In addition, the shoulder pivot of the seated Hybrid III 5thfemale ATD 305 is referred to as 206, the shoulder pivot of the seatedHybrid III 50th male ATD 405 is referred to as 206′, and the shoulderpivot of the seated Hybrid III 95th male ATD 505 is referred to as 206″.This common boundary of the zone Z may also serve as a reference axis.Also, in this embodiment, the portions of the body located above therespective shoulder pivots on ATD's 305, 405 and 505 are considered todefine the respective head and neck regions of the ATD's. FIG. 8 showscontact between the front or contact face of a deployed airbag 10 andthe divider leading edge seam 110 a positioned as just described, and aHybrid III 5th female ATD 305. FIG. 9 shows contact between a deployedairbag 10 of the same design shown in FIG. 8, and a Hybrid III 50th maleATD 405. It is seen that both of ATD's 305 and 405 contact the seam 110a connecting the divider leading edge 100 a to the airbag main panel 12within the zone Z previously described.

It has been found that connecting the divider leading edge 110 to themain panel 12 along a seam 110 a located at or below and proximate theupper limit of zone Z (i.e., the horizontal axis defined by the shoulderpivot 206′ of a seated Hybrid III 50th Male ATD 405) greatly reduces theneck extension moment (i.e., the tendency of the head and neck to rotatewith respect to the torso, about the neck-torso junction).

For example, for a seated Hybrid III 5th female ATD, it has been foundduring collision testing that, in an airbag embodiment in which at leasta portion of the divider leading edge is detached from the occupantcontact side of the airbag so as to form a gas flow passage along theoccupant contact side, the upper portion of the head of the ATD willcontact the relatively softer or more “deflatable” upper chamber 102,the portion of the ATD located below the chin contacts the relativelyhigher pressure lower chamber (after the pressure therein has beenraised by contact with the occupant and backflow into the upper chamberrestricted by the flow restriction valve), and the chin of the ATDcontacts a zone located in the upper chamber proximate the occupantcontact side gas flow passage and having an intermediate pressuresomewhere between the higher lower chamber pressure and the relativelylower upper chamber pressure.

Also, as the position of the divider connection seam 110 a along theoccupant contact face of the airbag is lowered, the head region of theATD is positioned relatively farther from the divider and deeper intothe relatively softer upper chamber. Thus, in this case, the head andneck regions are able to rotate to a relatively greater extentresponsive to the neck extension moment.

It has also been found desirable to, in conjunction with adjusting theposition of the leading edge seam 110 a, control the rate of gasbackflow from the lower chamber 104 into the upper chamber 102responsive to pressure resulting from occupant contact with the airbagexterior of the lower chamber. For example, in cases where the leadingedge seam 110 a is attached to the airbag at a relatively higherlocation, it may be desirable to structure the flow restriction valve topermit a relatively lower backflow gas rate. This permits a relativelyless rapid “deflation” of the lower chamber due to backflow, whichpromotes a more uniform deflation of the cushion and helps maintain aproportional support of the entire occupant along the airbag occupantcontact face. This aids in maintaining the body alignment along theplane P in the face of the relatively greater stiffness or level ofsupport for the head and neck region provided by the higher location ofthe seam 110 a.

Alternatively, in cases where the leading edge seam 110 a is attached tothe airbag at a relatively lower location, it may be desirable tostructure the flow restriction valve to permit a relatively greaterbackflow gas rate. This permits a relatively more rapid “deflation” ofthe lower chamber, which promotes a more uniform deflation of thecushion and helps maintain a proportional support of the entire occupantalong the airbag occupant contact face. This aids in maintaining thebody alignment along the plane P in the face of the relatively largerproportion of the body impacting the airbag along the exterior of therelatively softer upper chamber.

Thus, it has been found that by controlling the position of the leadingedge connection seam 110 a and the flow restriction valve structure asdescribed above, a controlled deceleration of the torso, neck and headregions of the occupant can be effected, and the effects of the neckmoment can be minimized or even eliminated for a given passenger size,vehicle configuration, and other application parameters, using knownanalytical methods and/or through iterative testing.

Referring now to FIGS. 26A and 26B, in accordance with certainembodiments described herein, it is possible to integrate a “sharedvolume” depending on the valve mechanism and dynamic configuration ofthe divider panel in the airbag. That is, the divider may be configuredand attached to the outer airbag panels so as to provide a degree ofslack in the portions of the divider not attached to the outer panels.This slack enables the unattached portion of the divider to move in thedirection of the lower chamber during initial filling of the airbag orwhen the upper chamber pressure otherwise exceeds the lower chamberpressure, and to move toward the upper chamber during loading of thelower portion of the airbag (or when the lower chamber pressureotherwise exceeds the upper chamber pressure). The shared volume may bedefined by the relationship:

V _(shared) =V _(upper P1) −V _(upper P2)

where V_(upper P1)=the volume of the upper chamber when the chamber isfully inflated and the divider is fully distended toward the lowerchamber, and V_(upper P2)=the volume of the upper chamber when the lowerchamber is fully inflated and the divider is fully distended toward theupper chamber.

When the cushion is deployed, the relative volumes of the chambers andthe pressures in the chambers will vary during cushion inflation.Initially, the upper chamber will fill as the cushion extends from itsstowed position to a deployed position. This is necessary to provideearly support for the head, as the thoracic region is initiallyrestrained by the seat belt. Filling and pressurization of the upperchamber causes the unattached central portions of the divider to deflecttoward lower chamber 104. As the upper chamber comes into position, gasflow to the lower chamber is increased from the upper chamber throughthe divider flow restriction valve(s) (as described herein). This gasflow causes the lower chamber to begin to fill. As the lower chamberfills, its pressure and volume also increase. At the same time, thepressure in the upper chamber is maintained by continued gas flow fromthe inflator. Flow into the lower chamber continues until the cushionreaches a state where the upper and lower chambers are in substantialpressure equilibrium.

Upon initial contact between the passenger's thorax and the portion ofthe airbag exterior of the lower chamber, the lower chamber pressureincreases due to pressure from the thoracic loading, forcing theunattached central portion of the divider to distend toward the upperchamber. If there is a relatively greater amount of slack in thedivider, the amount of time elapsed between passenger contact with thelower chamber and full pressurization of the lower chamber (whichprovides firm support for the passenger thorax) is also relativelygreater, as the unattached portion of the divider moves from a lowerlocation in the airbag toward the upper chamber. Conversely, if there isa relatively lesser amount of slack in the divider, the amount of timeelapsed between passenger contact with the lower chamber and fullpressurization of the lower chamber (which provides firm support for thepassenger thorax) is also relatively lower, as the unattached portion ofthe divider moves from the lower location in the airbag toward the upperchamber. Thus, as the value of V_(shared) increases, the general effectis to soften the initial contact between the passenger thorax and theportion of the airbag exterior of the lower chamber 104.

The ability to vent gas through the upper chamber vents 106 allows aninitially softer response to contact by the occupant's head, while thedivider flow restriction valve(s) 112 permit a backflow of gas into theupper chamber from the lower chamber, thereby helping to maintain theupper chamber gas pressure needed to support the head.

In addition, for a given application and during fabrication of theairbag, the flow characteristics of the upper chamber vents 106 and thedivider flow restriction valve mechanism(s) 112 are adjusted withrespect to each other such that alignment of the occupant's body withthe plane P (FIG. 4) is maintained during contact with the airbag.

Gas migrates from upper chamber to lower chamber during initial fillingthrough a flow restriction valve as described herein. Later, gas willmove back through the valve from the lower chamber to the upper chamberafter the lower chamber is filled and/or at the onset of loading by theoccupant. Depending on the state of filling of the chambers at a giventime in the event, the unattached portions of the divider panel willmove within the cushion (either in a direction toward the upper ortoward the lower chamber) providing the tunable variable volumepreviously described. This provides a proportional restraint for boththe relatively lighter head and the relatively heavier thorax whichhelps to minimize the differential movement between the head and thethorax which would result in undesirable forces at the neck. As theoccupant loading continues and the gas from both chambers is expelledinto the vehicle interior through the upper chamber main vent, thisbalance between head and thorax restraint is maintained, resulting inlow differential movement between the head and thorax and more favorableoccupant neck performance.

Stated another way, the flow control characteristics of the dividervalve(s) 112 and main vent(s) 106, and the divider configuration andattachment of the divider to airbag exterior panels 12, 14 and 16 arespecified so as to regulate gas flow through the valve(s) 112 andvent(s) 106 during the various stages of occupant contact with thecushion, so that the portions of the upper and lower chambers of thecushion facing the occupant 20 form and maintain an essentially flatplane, indicated by the line P in FIG. 4, during contact with theoccupant. The upper and lower chamber pressures are regulated by thevalve and vent flow characteristics so that the cushion supports theoccupant in a manner required to maintain the head-thorax alignmentshown in FIG. 4 during occupant contact with the cushion. This providesthe desired low differential movement between the head and thorax. Thevalve and vent design parameters required to provide the desiredresponse to cushion loading for a given requirement may be determinedanalytically and/or iteratively through experimentation.

The ability to control the geometries or shapes of the upper and lowerchambers as defined by the outer panel and divider panel configurationsand the divider panel attachment, and the ability to control the flowcharacteristics of the valves 112 and vents 106 are important inachieving the desired optimum cushion performance, because appropriateselection of these parameters enables the desired adjustment ofpressures and pressure distributions within the airbag responsive toloading by contact with the vehicle occupant head and thorax regions.

A desired relationship between upper and lower chamber volumes and valveand vent flow characteristics for a particular application is affectedby the vehicle interior general arrangement, including the windshieldangle, the profile of the instrument panel, and other interior features,and also by the position and size of the occupant (as determined bytesting with ATD's per the applicable standards) and the projectedmovement of the occupant after a collision, (which is, in turn isaffected by such factors as the crash pulse and the energy managementperformance of the seatbelt, for example). These factors are allconsidered in developing the specific upper and lower chamber volumesand valve and vent flow characteristics for a given application.

In certain embodiments described herein, an inter-chamber venting systemis provided to permit gas to flow from the upper chamber into the lowerchamber, and also for controlling or restricting backflow from the lowerchamber 104 into the upper chamber 102. In one embodiment, a flowrestriction valve 112 (shown schematically in the drawings) isincorporated into or otherwise operatively coupled to divider 100 forcontrolling flow between the upper and lower chambers. The valve isstructured such that an actuation response time of the valve inattenuating or impeding gas flow from lower chamber 104 into upperchamber 102 is proportional to the pressure differential between theupper and lower chambers. The valve is also structured such that abackflow rate of gases through the valve and into the upper chamber isproportional to the pressure differential between the upper and lowerchambers.

In operation, as the vehicle occupant begins to load the lower chamber104 of the cushion, the pressure within the lower chamber increases,causing the operating member of the valve mechanism 112 to close,thereby restricting the backflow of gas from the lower chamber to theupper chamber. This restricted flow now is effectively absorbing energyfrom the occupant interaction with the bag. The flow restriction canalso be adjusted or tuned in order to absorb the occupant energy asrequired in a particular application. The directional or flowrestriction valve mechanism 112 controlling flow between the upper andlower chambers can have a single operating member which permits both adesired inflow (to the lower chamber) and which is operable to restrictbackflow through the opening 200 and into the upper chamber in a desiredmanner, responsive to a pressure differential wherein the lower chamberpressure exceeds the upper chamber pressure. Alternatively, as seen inthe valve embodiment shown in FIGS. 19-22B (described in greater detailbelow), the valve mechanism can have one operating member forcontrolling flow into the lower chamber 104 and another operating memberto restrict backflow from the lower chamber into the upper chamber. Inthe later phases of the occupant loading of the cushion, backflow fromthe lower chamber goes into the upper chamber and then the gas isdischarged from the upper chamber into the environment through the mainvents (not shown) located in the wall of the upper chamber.

In particular embodiments, it may be desirable to more tightly andflexibly control the gas flow from the upper chamber to the lowerchamber, and then, from the lower chamber to the upper chamber.Accordingly, FIGS. 19-22B illustrate a divider and a particular flowrestriction valve embodiment that facilitates the flow of gas from theupper chamber to the lower chamber, and then, from the lower chamberback to the upper chamber. Accordingly, an object of the embodiment ofFIGS. 19-22B, but not by way of limitation, is to provide apredetermined equilibrium between the pressures in the upper and lowerchambers. A detailed description of this valve embodiment is provided inpending U.S. application Ser. No. 14/249,930, the disclosure of which isincorporated by reference herein in its entirety.

In the embodiment shown in FIGS. 19-22B, a directional fabric two-wayvalve 312 is sewn or otherwise attached to a divider panel 300(constructed as described above) and connects the upper and lowerchambers to facilitate fluid communication between the upper chamber 302and the lower chamber 304. A main orifice 306 is formed within thedividing panel 300 and facilitates the initial flow of inflator gas fromthe upper chamber 302 to the lower chamber 304. A first valve cover 308is preferably formed from the same fabric as the divider 300, wherebythe first valve cover 308 is attached to the underside of divider panel300 along first divider attachment regions 310, to at least partiallycover the main orifice 306. First gas pathways 315 are defined by theresultant interface defined between the first valve cover 308 and thedivider panel 300, whereby initial gas flow from the upper chamber 302is diverted or channeled through the first gas pathways 315 about thefirst valve cover 308 and into the lower chamber 304.

A second orifice 314 is formed in the first valve cover 308 therebyproviding fluid communication from the lower chamber 304 back into theupper chamber 302 subsequent to the initial transfer of gas from theupper chamber to the lower chamber. A second valve cover 316 is sewn orotherwise attached to the first valve cover 308 along second attachmentregions 316 a, to at least partially cover the second orifice 314.Second gas pathways 320 are defined by the resultant interface definedbetween the second valve cover 316 and the first valve cover 308,whereby secondary gas flow from the lower chamber 304 is channeledthrough the second gas pathways 320 through the main orifice 306 andback into upper chamber 302.

In operation, an associated inflator (not shown in FIGS. 19-22B, butexemplified in the other embodiments and in the prior art) is actuatedupon a crash or collision event. Inflation gas initially fills the upperchamber 302 and then flows through the main orifice 306 and throughfirst gas pathways 315, and then into lower chamber 304. As pressureincreases within the lower chamber 304, the first valve cover 308 isresponsively designed to cover the main orifice 306 thereby attenuatingthe backflow from the lower chamber 304 back into the upper chamber 302,and simultaneously and substantially restricting the gas flow throughfirst gas pathways 315. However, once the occupant (not shown) makesphysical contact with the airbag, the outer pressure from the occupantincreases the gas pressure within the lower chamber 304. The increasedpressure within lower chamber 304 exerts a force on the second valvecover 316 through opening 314 that “lifts” the second valve cover 316from the normally closed and flush position over the second orifice 314.As the second valve cover 316 is “lifted” as shown in FIG. 22, asecondary gas flow is facilitated through second gas pathways 320 andthen upward and into first chamber 302.

In sum, the embodiment of FIGS. 19-22B provides an alternate inflationprofile of the airbag 30 as compared to the other embodiments shownherein, whereby the inflation pressure may be softened over time therebyaffecting a softer deployment if desired.

In addition, as the cross-sectional areas of first gas flow pathways 315are greater than the cross-sectional area of return or backflow pathway320, and because the cross-sectional area of opening 314 and/or thecross-sectional areas of first gas flow pathways 315 may be varied inaccordance with the requirements of a particular application, thevolumetric gas flow rates along each pathway may be controlled asdesired to facilitate desired airbag deployment and response profiles.

In the case of an Out of Position child in accordance with the NHTSAPosition-2 testing standard, the initial stages of the cushiondeployment development remains the same as described above. However, thegas flow between the upper and lower chambers as regulated by thedivider valve mechanism is different when a child interacts with thecushion. In the case of the Out of Position-2 child, the volume of thelower chamber is decreased due to the space occupied by the Out ofPosition Child. The divider valve mechanism continues to permit the flowof gases from the upper chamber into the lower chamber. However, thevalve mechanism also allows the gas to continue to flow into the lowerchamber until the cushion's lower chamber and upper chamber internalpressures are in equilibrium, thereby stabilizing the interactionbetween the cushion and the out of position child. The divider valvemechanism 112 and cushion main vent designs are structured to facilitaterapid transition of this state of equilibrium into an adaptive state,wherein the cushion changes from a state of gas flow into the lowerchamber to a state where the gas flow is increased out of the main vents(located in wall(s) of the upper chamber) into the environment. Thisincreased flow out of the cushion allows for decreased pressure withinthe upper chamber and then allows for the backflow of gases from thelower chamber back into the upper chamber and out of the main vents intothe environment. This adaptability of the valve mechanism 112 toregulate the flow communication between the two chambers is importantfor the protection of adult and child occupants.

In sum, the particular valve embodiment described above may becharacterized as:

an airbag comprising a first chamber and a second chamber;

a perforated dividing panel attached to an inner wall of the airbagthereby providing said first chamber and said second chamber, saidperforated dividing panel containing at least one main orifice;

a valve for one-way or two-way fluid communication between said firstchamber and said second chamber, the valve providing fluid communicationthrough said at least one main orifice;

a first valve cover attached to said dividing panel for covering said atleast one main orifice, said first valve cover facilitating fluid flowfrom said upper chamber to said lower chamber and attenuating fluid flowfrom said lower chamber into said upper chamber;

at least one optional second orifice formed in said first valve cover,said second orifice selectively sealed during actuation of said airbag;and

an optional second valve cover attached to said first valve cover forcovering said at least one optional second orifice, said optional secondvalve cover facilitating fluid flow from said lower chamber into saidupper chamber.

Valve 112 may have any of a number of alternative structures suitablefor controlling gas flow in the airbag interior, in the manner describedherein. In one embodiment, the valve has the structure shown in U.S.Pat. No. 5,246,250, the disclosure of which is incorporated herein byreference in its entirety. In another embodiment, the valve has thestructure shown in U.S. patent application Ser. No. 14/452,016, thedisclosure of which is incorporated herein by reference in its entirety.In another embodiment, the valve has the structure shown in U.S. PatentApplication No. 61/865,095, the disclosure of which is also incorporatedherein by reference in its entirety. Other suitable valve structures arealso contemplated. The gas flow rate from the upper chamber 102 into thelower chamber 104 may be controlled in a known manner by controlling thevalve structure and dimensions.

In additional embodiments of the airbag, a valve 112 suitable forcontrolling gas flow in the airbag interior may have one of thestructures shown in U.S. patent application Ser. No. 14/458,153, thedisclosure of which is incorporated herein by reference in its entirety.

Referring now to FIGS. 28 and 29, in another particular embodiment ofthe airbag, a divider 300 has attachment portions 310 and non-attachmentportions 313 and 315. Attachment portions 310 are attached to the panels12, 14 and 16 forming an exterior of the airbag so as to form gas tightseals between the divider and the panels, as previously described.Non-attachment portions 313 and 315 are unattached to any of panels 12,14 and 16, so that openings or slits 320 and 322 are formed between thenon-attachment portions 313 and 315 and the portions of the panels 12,14 and 16 opposite the non-attachment portions 313 and 315. Slits 320and 322 enable fluid communication between the upper and lower chambers102 and 104.

Referring to FIGS. 28 and 29, in a particular embodiment, flaps 312 band 321 b are formed integrally with (or otherwise attached to) divider300 by cutting a piece of material forming the divider to a desiredshape (for example, the shape shown in FIG. 29 or a similar shape). Thispermits the attachment portions 310 formed on either side of each offlaps 312 b and 321 b to be attached to one or more of the outer airbagpanels, while the non-attachment portions 313 and 315 reside spacedapart from or opposite respective ones of the outer airbag panels. Atthe same time, flaps 312 b and 321 b hang from the divider 300 andextend into lower chamber 104. Flaps 312 b and 321 b are alsodimensioned and otherwise structured so that they are forced in adirection toward slits 320 and 322 and/or toward and into contact withthe respective airbag exterior panels opposite which they reside,responsive to an airbag pressure differential which tends to force abackflow of gases from lower chamber 104 toward upper chamber 102. Inthis manner, flaps 312 b and 321 b at least partially occlude or blockthe slits 320 and 322, thereby restricting backflow through the slits inthe manner described in U.S. patent application Ser. No. 14/458,153,which is incorporated herein by reference.

In the particular embodiment shown in FIGS. 28 and 29, the divider 300is structured and attached to the airbag exterior panels 12, 14 and/or16 so that each of non-attachment portions 313 and 315 forms a straightline extending between adjacent portions of the divider attached to theexterior panels when the airbag is inflated. In this embodiment, flaps312 b and 321 b extend from the non-attachment portions 313 and 315 intothe lower chamber 104.

In particular embodiments, portions of the flaps 312 b and 321 b arestitched or otherwise suitably attached to one or more of airbagexterior panels 12, 14 and 16, to aid in preventing the flaps from beingforced through openings 320 and 322 and into upper chamber 102responsive to a pressure surge in lower chamber 104.

In one particular embodiment, at least portions of side edges 312 r and321 r of the flaps are attached to associated ones of airbag panels 12,14 and 16. The attachment may be along the entire lengths of the sideedges, so as to form gas tight seals between the exterior panels 12, 14,16 and the flap side edges attached thereto. The locations andstructures of the side edges attachments are configured to enable atleast portions of the associated flaps to contact the airbag outerpanels 12, 14, 16 so as to form the desired seals to restrict backflow,as previously described. The flaps may be attached to any of the airbagpanels 12, 14 and/or 16 in any desired manner and at any desiredlocation(s) along the flaps. In one embodiment, the lengths of flaps 312b and 321 b from the divider 300 to the ends of the flaps is at least 4inches.

Referring now to FIGS. 27 and 43-47A, in particular embodiments, atleast a portion of the divider leading edge is unattached or spacedapart from the occupant contact side of the main panel. This provides agas flow opening opening between the divider leading edge and theoccupant contact side of the main panel which enables fluidcommunication between the upper and lower chambers when during airbaginflation and prior to contact with the occupant. The remaining edges ofthe divider 800 are attached to one or more of panels 12, 14 and 16 soas to form substantially gas tight seals between these attached edgesand the associated panels, as previously described. The unattacheddivider edge(s) may extend from a main portion of the divider to formassociated flap(s) positioned opposite the occupant contact side andextending into the airbag lower chamber, similar to the flaps shown inFIGS. 28 and 29. These structures thus form flow restriction valvemechanisms similar to that shown in FIGS. 28 and 29, with an openingenabling fluid communication between the upper and lower chambers.Alternatively, one or more portions of the divider leading edge may beunattached and (optionally) spaced apart from the occupant contact sidewithout incorporating a flap therein. In these embodiments, the area ofthe flow passage between the divider leading edge and the occupantcontact side is controlled after airbag deployment by direct occupantcontact with the occupant contact side, which closes the gas flowopening to a degree dependent on the contact force exerted by theoccupant.

A feature provided by divider-edge gas flow passages formed by leavingat least a portion of the divider unattached to another airbag panel(and, in particular, by a leading edge gas flow passage formed byleaving at least a portion of the leading edge unattached to theoccupant contact side) is a continuous gas flow channel extending alongthe inner surface of the main panel through both the upper and lowerchambers.

In addition, the opening and valve mechanism (if any) controlling flowbetween the upper and lower chambers is at least partially defined bythe occupant contact surface, enabling the valve mechanism to actuatedand/or the gas flow opening to be restricted or closed by direct contactof the occupant with the occupant contact surface.

In addition, the speed with which, and amount by which, the gas flowopening is restricted or closed by direct occupant contact is affectedby the contact force between the occupant and the contact side, whichdirectly affects the speed and degree of deflection of the contact side.

In another particular flow restriction valve embodiment shown in FIG.27, one or more valves 312 structured as shown in FIGS. 28 and 29 areformed at the seam(s) between the divider 300 and the main airbag panel,in a frontal region of the bag first contacted by a passenger 702 duringor after bag inflation.

In this embodiment, the divider 300 has at least one non-attachmentportion 313 structured to form an associated at least one slit 320between the non-attachment portion 313 and the portions of the mainpanel 12 residing opposite the at least one non-attachment portion 313.Slit 320 enables fluid communication between the upper and lowerchambers 102 and 104.

In addition, a flap (not shown) as previously described with regard toFIGS. 28 and 29-may be formed integrally with (or otherwise attached to)divider 300 by cutting a piece of material forming the divider to adesired shape in which the flap extends from the associated at least onenon-attachment portion 313, as described previously with regard to FIGS.28 and 29.

In this embodiment, the valve structure can be tuned or tailored so thatthe effectiveness of the seal formed between the flap and the bag outerpanel opposite the flap is related to the mass of a passenger 702impacting the airbag on the occupant contact side. When the passengerimpacts the airbag, there is a pressure surge in lower chamber 104tending to force gases from the lower chamber back through the valve 312and into the upper chamber. This pressure tends to force the valve flapinto contact with the opposing exterior airbag panel, as previouslydescribed. In addition, the contact of the passenger with the exteriorairbag panel 12 tends to push the contacted portion of the panel in thedirection of arrow “G”, toward and into the outwardly-moving valve flap.The greater the mass of the passenger, the greater the inward forceexerted on the bag panel 12 and the greater the pressure surge in thelower portion of the bag. As the magnitudes of the opposing forcesacting on the valve flap increase, the flap is forced more tightlyagainst the airbag panel, thereby increasing the effectiveness of theseal formed therebetween. In addition, the size and/or shape of theopening 320 may be tailored to control such factors as the backflow rateof gases therethrough, the amount by which the opening 320 is blocked,the amount of deflection of the occupant contact face required to closethe opening a given amount, and other pertinent factors.

Also, in embodiments incorporating a gas flow passage between thedivider leading edge and the occupant contact side of the airbag as justdescribed, while gas flows freely from the upper chamber prior tocontact between the passenger and the airbag and is restricted afterpassenger contact as described herein, gas backflow from the lowerchamber into the upper chamber may increase later in the loadingsequence, due to a reduction in loading energy by the passenger as thisenergy is absorbed and dissipated by the airbag.

Also, in embodiments incorporating one or more gas flow passages betweenthe divider leading edge and the occupant contact side of the airbag asjust described, the flaps may be omitted from the gas flow openingdepending on the requirements of a particular application, if sufficientclosure of the gas flow passage can be obtained as a result of pressureexerted by the occupant when contacting the occupant contact side of theairbag and pressing this side inwardly, as described herein.

Referring now to FIGS. 43 and 44, in particular embodiments, an entirelength of the divider leading edge 800 a positioned adjacent or oppositethe occupant contact side 812 a of the airbag is unattached or spacedapart from the occupant contact side 812 a of the main panel 812. Thispermits provides an opening between the divider leading edge and theoccupant contact side of the main panel which enables fluidcommunication between the upper and lower chambers when the airbag isinflated and prior to contact with the occupant. The remaining edges ofthe divider 800 are attached to the side panels 814 and 816 and to aside 812 z of the main panel opposite the occupant contact side 812 a soas to form substantially gas tight seals between these edges and theassociated panels, as previously described. Unattached edge 800 aextends from a main portion of the divider 800 to form a free-hangingflap positioned opposite the occupant contact side and extending intothe airbag lower chamber, similar to the flaps shown in FIGS. 28 and 29.The structure shown in FIGS. 43 and 44 thus forms a flow restrictionvalve mechanism similar to that shown in FIGS. 28 and 29, with anopening 829 enabling fluid communication between the upper and lowerchambers.

During inflation of the airbag, gases may flow freely through the valveopening 829 from the upper chamber 102 to the lower chamber 104, as inthe valve embodiments previously described. The valve opening 829 formedby the space between the flap 800 a and the occupant contact side 812 ais also at least partially closable as previously described (to restrictbackflow from the lower chamber into the upper chamber) by pressureexerted by the occupant when contacting side 812 a (i.e., backflowthrough the valve mechanism is restricted by contact between theoccupant and an exterior surface of the airbag and/or by pressureexerted by the occupant on the airbag which urges a portion of theairbag toward the airbag interior). The increased pressure in the lowerchamber acts to urge the flap 800 a toward an airbag exterior panel, aspreviously described. FIGS. 46 and 46A show schematic cross-sectionalside views of the embodiment shown in FIGS. 43 and 44, with the valvemechanism in an open (FIG. 46) and a closed (FIG. 46A) condition. Thisembodiment of the divider 800 may also, if desired, incorporate one ormore valve mechanism(s) 840 spaced apart from the edges of the dividerand structured and/or located in accordance with one of the other flowrestriction valve embodiments described herein.

Referring now to FIGS. 45 and 45A, in particular embodiments similar tothat shown in FIGS. 43 and 44, the divider edge 800 a′ positionedadjacent or opposite the occupant contact side 812 a of the airbag mayincorporate one or more attachment portions 819 alternating with one ormore adjacent non-attachment portions 809. In one embodiment, a flap 809a is formed along each of the non-attachment portions as previouslydescribed. The flaps 809 a extend into the lower chamber 104. Extendingbetween each non-attachment portion 809 and the occupant contact side812 a is a gas flow passage 829′ enabling fluid communication betweenthe upper and lower chambers. The embodiment shown in FIGS. 45 and 45Ashow an attachment region 819 and a non-attachment region 809 alongeither side thereof. However, any arrangement of attachment regions andassociated non-attachment regions may be employed, according to therequirements of a particular application.

The remaining edges of the divider 800′ are attached to the side panels814 and 816 and to a side 812 z of the main panel opposite the occupantcontact side 812 a so as to form substantially gas tight seals betweenthese edges and the associated panels, as previously described.

The divider may be attached at any desired locations and number oflocations along the occupant contact side 812 a, to provide anyassociated desired number of flow passages. In addition, each of theconnected regions may have any desired length extending along theoccupant contact side 812 a. The structure shown in FIGS. 43 and 44 thusprovides a series of flow restriction valve mechanisms similar to thatshown in FIGS. 28 and 29.

During inflation of the airbag, gases may flow freely through the valveopenings 829′ from the upper chamber to the lower chamber, as in thevalve embodiments previously described. The valve openings 829′ formedby the space between the flaps 809 and the contact side 812 a are alsoclosable as previously described (to restrict backflow from the lowerchamber into the upper chamber) by pressure exerted by the occupant whencontacting side 812 a (i.e., backflow through the valve mechanism isrestricted by contact between the occupant and an exterior surface ofthe airbag and/or by pressure exerted by the occupant on the airbagwhich urges a portion of the airbag toward the airbag interior). FIGS.46 and 46A show cross-sectional side views of the embodiment shown inFIGS. 45 and 45A, with the valve mechanism in an open (FIG. 46) and aclosed (FIG. 46A) condition. This embodiment of the divider 800′ mayalso, if desired, incorporate one or more valve mechanism(s) 840 spacedapart from the edges of the divider and structured and/or located inaccordance with one of the other flow restriction valve embodimentsdescribed herein.

Referring to FIGS. 47 and 47A, in particular embodiments, the edge 702of the divider 700 closest to occupant contact side 712 a is unattachedto and spaced apart from the occupant contact side 712 a when the airbagis inflated and prior to contact with the occupant. These embodimentsmay be structurally and operationally similar to those shown in FIGS.43-46A, except that no flaps are formed along the edge 702.

During inflation of the airbag, gases may flow freely through the valveopenings 729 from the upper chamber to the lower chamber, as in thevalve embodiments previously described. The valve opening(s) 729 formedby the space between the divider edge 702 and the occupant contact side712 a are also closable as previously described (to restrict backflowfrom the lower chamber into the upper chamber) by pressure exerted bythe occupant when contacting side 712 a (i.e., backflow through thevalve mechanism is restricted by contact between the occupant and anexterior surface of the airbag and/or by pressure exerted by theoccupant on the airbag which urges a portion of the airbag toward theairbag interior). FIGS. 47 and 47A show cross-sectional side views ofthis embodiment, with the valve mechanism in an open (FIG. 47) and aclosed (FIG. 47A) condition. This embodiment of the divider 700 mayalso, if desired, incorporate one or more valve mechanism(s) (not shown)spaced apart from the edges of the divider and structured and/or locatedin accordance with one of the other flow restriction valve embodimentsdescribed herein.

The design parameters of the valve embodiments shown in FIGS. 43-47A canbe iteratively determined (experimentally and/or analytically) andspecified as previously described so as to regulate the amount of gasbackflow (if any) through the valve opening, responsive to the mass ofthe passenger and according to the requirements of a particularapplication.

Referring now to FIGS. 15-17, in particular embodiments, a valvemechanism 112 controls and provides a directional gas flow through oneor more openings 200 (for example, opening 200 as shown in FIGS. 3, 15,16A, 16B and 17) formed in divider 100. Opening(s) 200 are provided toenable fluid communication from upper chamber 102 into lower chamber 104as previously described. It has been found that airbag performance afteractivation and during filling is affected by the distance (or distances)100 f of the opening(s) 200 from the inflator side 100 d of the airbag(as seen in FIG. 16 a), and also by the distance (or distances) of theopening(s) 200 from the front or passenger side 100 a of the airbagalong an axis extending parallel to the fore-aft axis of the vehicle.More specifically, if leading edge 200 a of the openings 200 (or theleading edge of any opening, if multiple openings are used) is locatednearer to the occupant contact side of the cushion than a location 100 jdefined by a predetermined distance D1 from the occupant side (asmeasured from the seam connecting the divider 100 with the front portionof main panel 12 and along a surface of the divider), the airbag willhave a tendency to pull excessively downward during inflation of theupper chamber 102, thereby pulling the airbag out of the desiredalignment with the passenger's body shown in FIG. 4, prior to contactbetween the passenger and the inflating airbag.

Also, if an edge 200 b of the opening 200 (or an edge of any opening, ifmultiple openings are used) closest to the inflation side 100 d of theairbag, is located closer to the inflation side 100 d than a location100 h (residing a predetermined distance 100 f along the a surface ofthe divider 100 from the inflator side 100 d), the movements of thecomponents of the valve mechanism 112 may be constricted by proximity tothe instrument panel profile (denoted by line 212 in FIG. 16A), therebyimpairing valve operation.

It is also desirable to achieve adequate gas flow to fill lower chamberwithout having the upper chamber pressure become too high to meet theNHTSA airbag performance requirements for an out-of-position 3 year oldor 6 year old child, evaluated for position-1, with the torso of thechild positioned in relation to the instrument panel as shown in FIG.49. Position-1 for Out of Position testing is also shown in FIG. 5 ofthe reference available athttp://www.nhtsa.gov/cars/rules/rulings/80g/80giii.html, the substanceof which is repeated as FIG. 49.

While positioning of the divider opening edge(s) 200 a (closest to thepassenger contact side) past the distance D1 along the divider andfarther away from the passenger contact side of the main panel 12 helpsto eliminate excessive downward pull of the airbag during the initialstages of inflation, thereby improving the overall performance of thebag with respect to an adult occupant, this positioning of theopening(s) may result in less-than-optimum performance for Out ofPosition-1 children. There is a balance between these requirements whichmay be tuned for a specific vehicle or specific application in order toachieve the best overall performance both early and later in thedeployment event, and for both types of passenger, children and adults.Between locations 100 h and 100 a lies an optimal location or locationsfor tuning the initial cushion fill and cushion pitch to achieve thedesired results for a given application. The exact desired location ofthe opening (or openings) 200 for a particular application may bedetermined iteratively, by experimentation, or analytically.

Thus, between locations 100 h and 100 j along a surface of the divideris an interval or zone in which all edges of the opening or openings 200should be positioned to prevent excessive downward pull of the airbagduring inflation and to space apart the flow restriction valvecomponents from the instrument panel. By positioning the valve mechanismwithin the range defined by locations 100 h and 100 j, the force exertedby the inflated airbag on 3 & 6 year olds in position-1 will be equallydivided between the child's head and thorax regions.

Also, in particular embodiments of the airbag, it is desired to positionthe opening(s) 200 along the divider 100 so that, during inflation, theairbag 10 reacts with a child passenger in a predetermined manner. Morespecifically, the opening(s) 200 are positioned along the divider suchthat, as the upper chamber fills in the initial stage of deployment, thebag upper chamber 102 inflates above the top of the head 700 a of aHybrid III 3 and 6-Year Old Anthropomorphic Test Device (ATD) (generallydesignated 700) when the head is positioned resting against or proximatethe vehicle instrument panel at a location specified as Position-2 forNHTSA Out of Position (OOP) testing in accordance with FMVSS StandardNo. 208 (which is incorporated herein by reference in its entirety andwhich may be found, for example, athttp://www.fmcsa.dot.gov/rules-regulations/administration/fmcsr/fmcsrruletext.aspx?reg=571.208).The Hybrid III 3 and 6-Year Old test ATD has physical parameters definedby the National Highway Traffic Safety Administration athttp://www.nhtsa.gov/Research/HYBRID+III+6-Year+Old+Physical+Data, thecontents of which is incorporated by reference in its entirety, and acopy of the substance of which is included herein as FIG. 18 a.Position-2 for Out of Position testing is also shown in FIG. 5 of thereference available athttp://www.nhtsa.gov/cars/rules/rulings/80g/80giii.html, the substanceof which is repeated in this application as FIG. 18B. As gases flow intothe lower chamber 104 from the upper chamber 102, the lower chamber 104inflates in the later stages of deployment so as to occupy a spacebehind and around the child's head, thereby preventing and/or mitigatingharmful interactions between the airbag and the child's head. Thisinflation progression is shown in FIGS. 16 and 17.

It has been found that an optimum inflation profile range and alignmentwith the passenger's body as shown in FIG. 4, as well as the baginflation progression shown in FIGS. 16-17, can be achieved bypositioning all divider openings 200 such that all edges of all theopenings reside within the zone bounded by or residing between locations100 h and 100 j in FIG. 16A, which may also be defined on one side by avertical plane P1 shown in FIG. 16 corresponding to location 100 h inFIG. 16 b abutting the front-most portion of the head of the Hybrid III6-Year Old Anthropomorphic Test Device when the head of the Hybrid III6-year old is in Position-2 for NHTSA Out of Position testing asspecified above, and on an opposite side by a vertical plane P2 (seeFIG. 16) passing through location 100 j shown in FIG. 16 b. In oneembodiment, plane P2 is spaced apart approximately 7 inches from planeP1 toward a rear of the vehicle when the airbag is inflated. Thiseffectively positions the divider opening(s) within a zone enclosing thehead of the Hybrid III 6-Year Old ATD. The distance between planes P1and P2 defines a zone Z3 in which the openings 200 may be positioned.For example, FIG. 15 is a plan view of an uninflated airbag showing anembodiment of the airbag divider 100 having a circular opening 200positioned such that the rear-most edge of the opening resides withinthe specified zone Z3 when the bag is inflated.

It has also been found that a total area of the opening (or openings)200 within a range of 700 square millimeters (achievable using, forexample, one opening of approximately 15 mm radius) to 32,000 squaremillimeters (achievable using, for example, one opening of approximately100 mm radius opening) is desirable for helping to ensure that airbagperformance is within an optimum range. In embodiments of the presentinvention, which use a directional valve mechanism to facilitate inflowand restrict backflow from the lower chamber to the upper chamber aspreviously described, the areas of the divider opening or openings mayneed to be at or near an upper end of this range of opening sizes 700 to32,000 square millimeters, to provide the necessary inflation profilegiven the reduction in flow caused by turbulence and friction in thegases as they flow through the opening(s) and interact with the portionsof the valve.

In one embodiment, the opening or openings 200 are circular. However,the opening(s) can have any desired shape, as long as the total area ofthe opening(s) is within the range specified above, and as long as allof the opening edges are positioned within the zone defined above.

In addition, the number of openings 200 and the optimum size(s) of theopening(s) formed in divider 100 for a particular application may bedetermined based on the type of vehicle collision pulse and interiorgeometry of the vehicle in which the airbag is installed, the desiredfill rate of the airbag, the volume ratio, the type of directional valveused, the overall dimensions and curvature of the instrument panel, andother pertinent factors. The size(s) and position(s) of the opening(s)200 as described herein facilitate smooth and rapid transfer ofinflation gases from the upper chamber to the lower chamber duringinitial stages of airbag filling. Once equilibrium is substantiallyreached between the upper and lower chamber pressures, flow from onechamber to the other is reduced.

FIGS. 15-17 thus show an airbag comprising at least one panel definingan interior of the airbag and a divider positioned in the interior so asto divide the interior into an upper chamber and a lower chamber, thedivider having at least one opening formed therealong, the at least oneopening being positioned such that all edges of the at least one openingreside within a zone (Z3) bounded by a first vertical plane (P1)residing a predetermined distance (1000 along the divider from aninflator side (100 d) of the airbag toward an occupant contact side ofthe airbag, and a second vertical plane (P2) passing through a location(100 j) defined by a distance (D1) along the divider from a seam (110 a)connecting the divider (100) with the occupant side of the airbag, afteractivation of the airbag.

In a particular embodiment of the airbag, the first plane (P1) may bepositioned so as to abut a forward-most portion of a head of a HybridIII 6-Year Old Anthropomorphic Test Device when the head is inPosition-2 for NHTSA Out of Position testing.

In a particular embodiment of the airbag, the second plane (P2) may bespaced apart approximately 7 inches from the first plane (P1) toward arear of the vehicle when the airbag is fully inflated.

In a particular embodiment of the airbag, the airbag may further includea plurality of openings formed in the divider 100, with each openingbeing positioned such that all edges of the opening reside within thezone (Z3) bounded by the first plane (P1) and the second plane (P2).

In a particular embodiment of the airbag, a total area of all of theopenings of the plurality of openings may be within the range 700 squaremillimeters to 32,000 square millimeters, inclusive.

In a particular embodiment of the airbag, a total area of the at leastone opening may be within the range 700 square millimeters to 32,000square millimeters, inclusive.

In addition, the airbag may be incorporated into a vehicle in any of avariety of forms. The airbag may also be incorporated into a vehicleoccupant protection system or airbag system.

Another enhancement to improve the performance of the chambered airbagis the addition of volume control mechanism (VCM) or tether within theupper chamber of the cushion. The function of the VCM is to controlupper chamber volume relative to that of the lower chamber. This causesgas to flow into the lower chamber at an earlier time than would be thecase without the tether, thereby forcing the lower portion of the airbaginto position relatively faster for protecting small occupants, asrepresented by the Hybrid III 5th female ATD. The VCM also controls theconfiguration of the inner chamber dividing panel 100 during and afterinflation, so as to maintain the position of the divider above the headof the 6 year old child ATD in position 2 of the low risk deploymentsection, as detailed in the Federal regulations (FMVSS 208).

In certain embodiments described herein, tether mechanisms positionedwithin the airbag upper chamber may be attached to the divider at anylocation within the zone Z3 defined herein with regard to FIGS. 16B and17. At the same time, the tether mechanisms are attached to any otherportion of the airbag located within the upper chamber and above thedivider, so as to prevent or reduce movement of unattached portions ofthe divider in a direction toward lower chamber 104.

In certain embodiments (such as FIGS. 23 and 23A) the tether(s) 507 areoriented substantially orthogonal or cross-wise to an axis X3 runningparallel to a fore-aft axis of the vehicle. Referring to FIG. 23, inaccordance with one particular embodiment, a tether or tethers 507 (inFIG. 23, tethers 517 b and 517 c) may, if desired, be dimensioned tobroadly cover an interim portion within the airbag 510 that extendsacross an interior of the airbag 510, whereby the tether width W may bedesigned to approach the width W2 (in a direction perpendicular tovehicle fore-aft axis X3) of an upper portion 511 of the main panel 512.By thereby directing the gas flow along inner side periphery regions ofthe upper chamber 502 a (i.e., between each of airbag side panels 514and 516 and opposite side edges of second tether 517 c connecting thedivider with the main panel above the divider), the central part of theupper chamber 502 a (between first and second tethers 517 b and 517 c)receives a flow of gas directed from the opposite edges of the tether517 b toward the flow restriction valve 513, a flow that may bedescribed as “cross-car” or orthogonal to axis X3 running parallel to afore-aft axis of the vehicle and which is indicated by arrow X1. As aresult, the lower chamber 504 fill time is effectively decreased withthe decrease of the tether length (defined as the shortest distancealong the tether between the divider and the main panel) and alsoeffectively decreased with the decrease of the tether width W. It willbe appreciated that the fill rate of the lower chamber 504 may beiteratively tailored by modifying the width W and or length(s) of thetether(s) 507 to alter the resultant gas flow directed toward the flowrestriction valve. In this way, the upper chamber 502 may be tailored toexhibit a relatively softer or more pliable inflation profile over time,thereby protecting the head of a smaller occupant that may come incontact with the deploying upper chamber 502 portion of the airbag 510.Tether embodiments as shown in and/or similar to that shown in FIG. 23are described in greater detail in U.S. patent application Ser. No.14/195,767, the disclosure of which is incorporated herein by referencein its entirety.

In another particular embodiment, tether 507 has the general structureshown in FIG. 23A. In this embodiment, tether 507, when suitablyattached to other portions of the airbag, has central portion 517 a, afirst portion 517 b extending from one end of the central portion, and asecond portion 517 c extending from an opposite end of the centralportion. An end of first portion 517 b is stitched or otherwise suitablyattached to a portion of main panel 512 residing in upper chamber 102.An end of second portion 517 c is stitched or otherwise suitablyattached to a portion of main panel 512 residing in upper chamber 102.In particular embodiments, the ends of the tether are attached to themain panel along seams 575 as shown in FIG. 23A, so as to form gas-tightseals along the seams. This enables the tethers to direct a flow of gasimpinging on the tether around side edges of the tether. However, inother embodiments, openings or slits may be formed in the seams 575 toenable gas flow through the seams. In addition, openings (not shown) mayalso be formed in the bodies of one or more of first and second portions517 b and 517 c, to enable a flow of gas through the openings. Thedimensions of such opening(s) may be specified according to therequirements of a particular application, and depending on such factorsas the desired flow rate(s) through the openings, the locations of theopening(s), and other pertinent factors. Also, the ends of either offirst and second tether portions 517 b and 517 c may alternatively beattached to either of airbag side panels 514 and 516 and main panel 512,if desired. Embodiments of the tether may be formed from the samematerial as any of the airbag panels or divider 100, or any of othersuitable material or materials. Tether embodiments as shown in and/orsimilar to that shown in FIG. 23A are described in greater detail inU.S. patent application Ser. No. 14/195,767, which is incorporatedherein by reference.

In certain embodiments shown herein, and referring in particular to theembodiment shown in FIG. 23A for purposes of description, the oppositeends of the tether central portion 517 a are anchored by attaching theseends to divider 500. In addition, central portion 517 a has an opening508 formed therein to enable a flow of gases through the central portionand through a flow restriction valve mechanism 512 provided in divider500, as previously described.

Referring to FIG. 24, in another embodiment, the tether or tethers 507 aand 507 b connecting the divider to the main panel may be attached tothe main panel 512 along seams that run generally parallel to or arealigned with the vehicle fore-aft axis, and at locations relativelycloser to a vertical plane 111 extending along a rearmost part of theinstrument panel (not shown). In doing so, the gas fill rate of thelower chamber 504 of the airbag 510, as gas travels through the flowrestriction valve 512 in the divider panel 500 from the upper chamber502 to the lower chamber 504, may be relatively reduced or delayed. FIG.24A shows a schematic cross-sectional side view of the embodiment shownin FIG. 24, with gases entering the airbag and flowing along the pathindicated by arrow 24G.

Alternatively, referring to FIG. 25, if desired, the tethers 507 a and507 b may be attached along the axis X3 at points relatively closer tothe rear of the vehicle and away from the instrument panel. In doing so,the gas fill rate of the lower chamber 504 of the airbag 510 isrelatively increased. In general, the tether(s) 507 a and 507 b arepreferably attached at points that fall within a middle portion 511 a ofthe upper portion of the main panel of the airbag 510 that ranges fromabout 25% to 75% of the length L of the airbag 510, as measured from avertical plane 111 extending along a rearmost portion of the instrumentpanel to the rearmost part of the airbag 510. Stated another way, thetethers 507 a and 507 b may more preferably be fixed at points rangingfrom about 100 to 700 millimeters from the front of the instrument panel111. FIG. 25A shows a schematic cross-sectional side view of theembodiment shown in FIG. 25, with gases entering the airbag and flowingalong the path indicated by arrow 25G. In general, the placement of thetether(s) 507 a and 507 b or, modifying the angle of the tethers 507 aand 507 b with regard to the instrument panel 111, facilitates forwardor rearward tilting of the one-way valve 512 (or modifying the pitch ofthe one-way valve) thereby respectively closing or opening the valve 500to a more direct flow of gas.

Any of the tethers connecting the divider to an other portion of theairbag above the divider may also be joined to each other by a joiningsection (for example, either of joining sections 507 c of FIGS. 24 and25) which is connected to and extends along the divider between theconnection tether portions. Thus, the tether may be formed from acontinuous strip which has a central portion extending along the dividerand a pair of end portions connected to the divider and extending fromthe central portion to attach to another portion of the airbag.

In particular embodiments, the tethers 507 a and 507 b shown in FIGS. 24and 25 may, for example, be attached to the airbag outer shell along theseams 570 and 572 that attach the side panels 514 and 516 to the mainpanel 512 of the airbag 510 in the upper chamber 502. In this way,manufacturing is simplified, for as the airbag panels 512, 514, and 516are sewn together, the tethers 507 a and 507 b may simultaneously beattached in predetermined positions along the seams 570 and 572.

In addition, a second or bottom end of first tether 507 a may beconnected to the divider 500 between side panel 514 and valve 512, and asecond or bottom end of second tether 507 b may be connected to thedivider 500 between side panel 516 and valve 512. In a particularembodiment, the connection points or seams of the first and secondtethers 507 a and 507 b at both ends of each tether all preferablyreside within one plane that intersects the connection points describedin this embodiment, but may be attached in a multi-plane configuration.Altering the attachment locations of each of tethers 507 a, 507 b alongthe respective seam 570, 572 to which each tether is attached (that ispositioning the tether attachment somewhere between 25% to 75% of thelength L of the airbag 510 defined between the front of the instrumentpanel plane 111 and the rearmost part of the airbag 510 (as shown inFIG. 25) It will be appreciated that each of the two tethers 507 a and507 b will be attached to its respective seam at a respective pointequidistant from the instrument panel 111, as a correlating point of theother tether 507. Stated another way, each one of tethers 507 a, 507 bwill be attached to its respective seam at a point that is substantiallyequidistant from the instrument panel 111 as the attachment point of theopposing one of tethers 507 a, 507 b. It will further be appreciatedthat moving the attachment points along each seam may alter the pitch ofthe valve orifice 506. For example, moving the attachment points of thetethers 507 closer to the instrument panel 111 will thereby generallyprovide a greater exposure of the valve 512 to direct gas flow with aresultant increased relative gas fill rate into the lower chamber. Onthe other hand, moving the attachment points of the tethers 507 furtheraway from the instrument panel and more rearward of the vehicle willthereby attenuate or limit the exposure of the valve to direct gas flowwith a resultant reduced relative gas fill rate into the lower chamber.

In other embodiments described herein, the tether generally connects thedivider 100 with another portion of the airbag located in upper chamber102 and residing above the divider when the airbag is inflated. Thus, asthe airbag inflates, the tether pulls upwardly on the divider andsupports the divider and controls portions of the divider fromencroaching into or moving toward lower chamber 104. In particularembodiments, a tether connects a central portion of the divider with anupper portion of main panel 12, within upper chamber 102. Referring toFIG. 31, in a particular embodiment, a tether 899 is attached to alocation on the divider which is the apex or relatively highest portion898 of the divider 100 when the bag is in an inflated condition.Referring to FIG. 30, in another embodiment, a tether 880 is attached toeither the main panel 12 or the divider 100 along (or proximate) a seam878 connecting the divider 100 to the front or occupant contact surfaceof the main panel. An opposite end of the tether is then attached toanother portion of the airbag located in upper chamber 102 and residingabove the divider when the airbag is inflated, to aid in minimizing orreducing downward deflection or intrusion of the divider into the lowerchamber while simultaneously pulling inwardly or restricting motion ofthe front surface of the main panel in a direction toward the occupantduring airbag inflation. Attachment locations of the various portions ofthe tether to the divider and the airbag exterior panels may bespecified so as to control the exterior shape of the airbag during andafter inflation. More specifically, in the manner described herein, thetether (or tethers) may be attached so as to force specific portions ofthe airbag interior to inflate before other portions or to otherwisevary the flow rates of gases into portions of the bag interior, tocontrol the direction of gas flow within the airbag interior, and tocontrol the amounts by which various exterior portions of the airbagextend or project outwardly during and after inflation. Examples ofembodiments in which exterior surfaces of the airbag are controlled inthis manner are shown in FIGS. 32, 36, 37, and 38.

Referring to FIGS. 25B and 25C, in particular embodiments, at least aportion of a leading edge of divider 1007 is detached from the airbagoccupant contact side 1012 as described elsewhere herein, to form a gasflow passage 1001. The detached portion of the divider may or may notinclude a flap structured for impeding backflow of gases into the upperchamber, as described herein. A tether 1007 is structured to connect thedivider 1100 to occupant contact side 1012 above the divider andproximate a location where the head of a vehicle occupant will contactthe occupant contact side.

In a particular embodiment, the tether 1007 is attached to the dividerat a location within the zone Z3 previously defined herein.

In a particular embodiment, the zone ZZ along the occupant contact sidewithin which the tether 1007 is attached thereto is defined by a band B9having a maximum width of 20 inches extending along a vertical plane L9defining a centerline of the deployed airbag, the band also encompassingor including the points or locations along which a seat-belted HybridIII 5th percentile female ATD, a Hybrid III 50th percentile male testATD, and a Hybrid III 95th percentile male test ATD will contact theoccupant contact side.

In particular embodiments, as well as an upper chamber tether 1007 anddetached leading edge divider in accordance with FIG. 25B, the airbagmay also include a lower chamber tether in accordance with any of theembodiments described herein (for example as shown in any of FIGS.32-39. Also, in particular embodiments, in addition to any or all of thefeatures just recited, the airbag may if desired further include a flowrestriction valve mechanism 1112 positioned within the zone Z3 ofotherwise spaced apart from attachment or non-attachment edges of thedivider, as described elsewhere herein.

Referring to FIGS. 32-38, in particular embodiments, internal tetheringis applied to reduce the chest compression experienced by adultpassengers impacting the airbag, while simultaneously maintaining theperformance requirements for Out of Position-2 Children as incorporatedin the previously-described Federal standard FMVSS208 relating tolow-risk deployment.

Referring to FIGS. 32-38, in particular embodiments of the airbag, it isdesired to structure and attach an internal tethering mechanism 990 tointerior surfaces of the airbag below the divider 100, so as to connecta part 994 of the front portion of main panel 12 to a rear portion 992of the main panel (and/or to a portion of one of the side panels). Sucha tethering mechanism can be structured to help ensure that, duringinflation, the airbag 910 reacts with a child passenger or an adultpassenger in a predetermined manner.

In one particular embodiment, the tethering mechanism 990 is attached tothe airbag panels such that, as the bag fills, a first dimple, recess ordepression 991 is formed in approximately the lower half of a centralportion of the occupant-facing exterior surface of main panel 12. Recess991 is positioned and structured to reside opposite and to encompass orsurround what would be the sternum areas of the Hybrid III 5thpercentile female ATD, the Hybrid III 50th percentile male ATD, and theHybrid III 95th percentile male ATD, as described herein. The tetheringmechanism 990 is structured so that the inflated and unconstrainedportions of the main panel surrounding the recess 991 form lobes 991 aengaging the chest portions of the ATD's along either side of thesternum areas. This aids in relieving contact stresses on the sternumwhile still providing cushioning and support of the chest area. Inparticular embodiments, the depth D10 of the recess is measured from asurface along a side of the recess which initially contacts the chest toone side of the sternum, to a forward-most portion of the recesspositioned closest to the instrument panel.

In one embodiment, tethering mechanism 990 is attached to the airbagexterior panels 12, 14 and 16 so as to have a hollow, generally tubularstructure (as shown in FIG. 33A) when the airbag is inflated. Thisstructure may have a body 900 a formed from a hollow wall, a first end990 b and a second end 990 c. Wall 990 a defines an interior 990 d ofthe tubular structure. The wall 990 d is attached along first end 990 bto the occupant contact side of the main panel 12 along a seam 990 e, bystitching or other suitable means. The seam attachment serves torestrict inflation and expansion of the attached portion of the mainpanel 12 during airbag inflation, such that dimple 991 is formed in theoccupant contact side of panel 12. This dimple forms a recess into whicha sternum portion of the occupant is received when the occupant contactsthe airbag. FIG. 35 is a cross-sectional plan view of the airbagembodiment shown in FIGS. 32 and 33.

Thus, the depression 991 is structured and positioned so as to provide arecessed region of the airbag which is out of contact with a sternum orcentral portion of the thorax of an adult passenger, while the portionof the thorax surrounding the sternum impacts the airbag regionssurrounding the depression. In this manner, the airbag regionssurrounding the depression absorb the impact energy prior to contactbetween the airbag and the sternum or central portion of the thorax. Thechest loading is thus transferred to the rib portion of the passenger'schest.

The seams along which the edges of attachment ends 990 a and 990 b areattached to the airbag panels may have any shape necessary for producinga recess of a particular desired size or configuration.

Referring again to FIG. 33, 33A and also to FIG. 39, in one particularembodiment, edges of wall 990 a along tethering mechanism second end 990c are attached to a side 12 z of the main panel 12 opposite the occupantcontact side so as to form a second cavity, recess, or dimple 993 whichis positioned and structured to receive therein the head of a Hybrid III6-Year Old collision ATD (not shown) when the head is positioned restingagainst or proximate the vehicle instrument panel at a locationspecified as Position-2 for NHTSA collision testing in accordance withFMVSS Standard No. 208, which is incorporated herein by reference in itsentirety. Position-2 for NHTSA collision testing may be found athttp://www.nhtsa.gov/cars/rules/rulings/80g/80giii.html, the substanceof which is repeated herein as FIG. 18. The Hybrid III 6-Year Oldcollision ATD has physical parameters defined by the National HighwayTraffic Safety Administration athttp://www.nhtsa.gov/Research/HYBRID+III+6-Year+Old+Physical+Data, thecontents of which is incorporated by reference in its entirety.

Attachment of the tethering mechanism second end 990 c to the main panelside 12 z serves to restrict inflation and expansion of a portion of themain panel side 12 z during airbag inflation, such that dimple 993 isformed in this side of panel 12. This dimple forms a recess into whichthe head of a child passenger in Position 2 is received during inflationof the airbag as described herein with regard to FIGS. 15-17, so as toinflate over and around the child's head. In particular embodiments, thedepth D11 of the dimple 993 is measured from a forward-most surface ofthe airbag along either side of the dimple.

As gases flow into the airbag, the lower portion of the bag inflatessuch that depression 993 receives the child's head, while relativelyraised or protruding lobe portions 993 a of the airbag defining theboundaries of the depression 993 act to envelop and cushion the sides ofthe child's head. An additional advantage of the cavity 993 is itsability to accommodate therein a portion of an infant (not shown)positioned in an infant carrier buckled to the passenger seat.

As stated previously, provision of a tethering mechanism 990 as shown inFIG. 36 effectively reduces the inflated volume of the lower chamber ofthe airbag and, thus, the total volume of the cushion. Due to thisreduction in volume, the lower chamber takes less time to fill andpressurize, thus reducing the time required to position the airbag. Inaddition, the amount of gas required to fill the airbag is reduced,while permitting an increase in the relative stiffness of airbagexterior of the lower chamber.

Referring to FIGS. 33B and 33C, in another embodiment, a tetheringmechanism 990′ is attached to the airbag exterior panels 12, 14 and 16so as to provide a recess or cavity 991′ as previously described, butextending continuously from the occupant contact side around the bottomportion of the airbag to the side of the airbag closest to theinstrument panel. This recess 991′ includes and incorporates both theoccupant contact recess 991 and the child-receiving recess 993previously described.

FIG. 34 is a cross-sectional plan view of another embodiment 990′ of thelower chamber internal tethering mechanism. In this embodiment, thetethering mechanism 990′ is attached to the airbag panels such that, asthe bag fills, a first dimple or depression 991′ is formed inapproximately the lower half of a central portion of the occupant-facingexterior surface of main panel 12. Depression 991′ is positioned andstructured to reside opposite and to encompass or surround what would bethe sternum areas of the Hybrid III 5th percentile female ATD, theHybrid III 50th percentile male ATD, and the Hybrid III 95th percentilemale ATD, as described herein. The tethering mechanism 990′ isstructured so that the inflated and unconstrained portions of the mainpanel surrounding the dimple 991′ form lobes 991 a′ engaging the chestportions of the ATD's along either side of the sternum areas. This aidsin relieving contact stresses on the sternum while still providingcushioning and support of the chest area.

In this embodiment, the tether 990′ has a body 990 a′, a first end 990b′ and a second end 990 c′ opposite the first end. In the embodimentshown, tether 990′ extends along a substantially vertical plane when theairbag is inflated. However, the tether may have any orientationnecessary to provide the desired restraint of the airbag exteriorsurfaces when the cushion is inflated. Tether body 990 a′ may be formedfrom a single flat piece of material or from one or more pieces of flatmaterial attached for example, end to end, to form a substantially flator planar structure. The first end wall 990 b′ is attached to theoccupant contact side of the main panel 12 along a seam by stitching orother suitable means, as previously described. The seam attachmentserves to restrict inflation and expansion of the attached portion ofthe main panel 12 during airbag inflation, such that dimple 991′ isformed in the occupant contact side of panel 12. This dimple forms arecess into which a sternum portion of the occupant is received when theoccupant contacts the airbag. Thus, the depression 991′ is structuredand positioned so as to provide a recessed region of the airbag which isout of contact with a sternum or central portion of the thorax of anadult passenger, while the surrounding portion of the thorax impacts theairbag regions surrounding the depression. In this manner, the airbagregions surrounding the depression absorb the impact energy prior tocontact between the airbag and the sternum or central portion of thethorax. The chest loading is thus transferred to the rib portion of thepassenger's chest. In particular embodiments, the depth D10 of thedimple is measured from a surface along a side of the dimple whichinitially contacts the chest to one side of the sternum to a portion ofthe dimple closest to the instrument panel.

In addition, if desired, a second depression 993′ for the head of aHybrid III 6-Year Old collision ATD as previously described may beformed by attaching tether second end 990 c′ to side 12 z of the mainpanel. In particular embodiments, the depth D11 of the dimple 993′ ismeasured from a forward-most surface of the airbag along either side ofthe dimple.

It will be appreciated that the depths D10 and D11 of the recesses 991and 993 formed in the airbag exterior surfaces can be controlled bycontrolling the position of the tether relative to airbag sides 12 a and12 z, and by controlling the length LT of the tether extending generallyalong an axis parallel with a fore-aft axis of the vehicle (for example,as shown in FIGS. 33 and 33A.

Provision of a tethering mechanism 990′ as shown in FIGS. 32-39effectively reduces the inflated volume of the lower chamber of theairbag and, thus, the total volume of the cushion. Due to this reductionin volume, the lower chamber takes less time to fill and pressurize,thus reducing the time required to position the airbag. In addition, theamount of gas required to fill the airbag is reduced, while permittingan increase in the relative stiffness of airbag exterior of the lowerchamber.

FIG. 39 shows a cross-sectional side view (similar to that shown in FIG.17) of an airbag in accordance with an embodiment as described withregard to FIGS. 32-36, with the airbag wrapped over the head 700 of aHybrid III 6-Year Old collision ATD.

FIG. 39A shows a schematic side view of an airbag 1300 in accordancewith an embodiment as described with regard to FIGS. 32-36, with theairbag wrapped over the head 1205 of an infant 1201 secured in arear-facing infant car seat 1203. In this embodiment, the head of theinfant is received in a recess 1302 (such as recess 993 previouslydescribed) as the airbag inflates above and over the top of the infant'shead in the direction indicated by arrow R, thereby helping to securethe child's head in position when the airbag is in the deployedconfiguration.

Operation of an airbag in accordance with an embodiment describedherein, and movement of an adult vehicle occupant's body prior to andduring contact with a deployed airbag is illustrated in FIGS. 4, 8, 9and 10-14. FIGS. 8 and 9 show portions of collision tests using ATD's305 and 405, respectively, meeting the specifications previouslydescribed, after deployment of the airbags and stoppage of passengerforward motion. FIGS. 10-14 show a typical deployment/passenger contactsequence using an airbag in accordance with an embodiment of the presentinvention.

Referring to FIG. 10, prior to bag deployment, an ATD 305, 405, 505 isseated and airbag 10 (not shown) is operatively coupled to an associatedgas generating system or other inflation fluid source (not shown), in amanner known in the art. The inflation fluid source may be operativelycoupled to a collision event sensor (not shown) that includes (or is inoperative communication with) a controller (not shown) which signalsactivation of the airbag system in the event of a collision. The airbagand its associated inflation means are configured to provide rapidinflation of the airbag (and especially upper chamber 102) so as quicklyengage and cushion the forward-moving head & neck region and (at aslightly later point in time) the thoracic region of the passenger,while utilizing a singular cushion volume to aid in reducing the inertiaof the individual. The thorax region of the passenger is initiallyrestrained by the seatbelt and receives additional support from thelower chamber once it is filled.

Referring now to FIGS. 11 and 12, when the system is activated,inflation gas flows from the inflation fluid source into upper chamber102, rapidly inflating the upper chamber to enable this chamber tointercept the forward-moving head and neck regions as early as possible(as seen in FIGS. 13 and 14), to aid in minimizing the momentum built upby the head and neck regions. At this early stage of airbag inflation,the occupant seatbelt tensions to maintain the occupant's lower thoracicregion in the seat. Inflation gas then flows from the upper chamber 102through valve 112 into lower chamber 104 to pressurize the lower chamberfor supporting the occupant thoracic region when the seatbelt tensionerreleases.

Referring to FIGS. 13 and 14, when the lower chamber is filled, valve112 actuates responsive to pressure in lower chamber 104 to attenuate orrestrict the flow of gas back into the upper chamber 102. Also, as seenin FIGS. 8, 9, 13 and 14, contact between the ATD's and the airbagleading edge 100 a occurs within respective zones Z defined by the hipand shoulder joint locations on the bodies of the ATD's as previouslydescribed. Referring to FIGS. 4, 8, 9, 13 and 14, it is seen that thedivider leading edge seam 110 contacts the passenger between the hippivot 202 of the passenger and the shoulder pivot 206′ of the passenger.

Referring to FIG. 13, as the passenger head region 302 contact theairbags, gases in the upper chamber are vented into the lower chamber ordischarged into the environment via upper chamber vents 106, resultingin a reduction of upper chamber pressure and a “softening” of bag frontsurface over the upper chamber responsive to contact with thepassenger's head regions. This softening aids in providing sufficientsupport to protect the occupant's head region, while helping to minimizethe contact forces between the head region and the airbag. Because ofvalve 112, the compression of the upper chamber may cause some increasein the pressure within the lower chamber 104 in response to the contactwith the passenger's head. This facilitates the maintenance of alignmentof the head and thorax along axis L (FIG. 4). Responsive to continuedforward motion of the passenger's body, the airbag continues tocompress, proportioning the airbag internal pressure between thechambers so as to aid in preserving alignment while passenger is loadingthe airbag.

Referring to FIG. 14, at a time later in the airbag loading event, thechest (thorax) engages the lower portion of the cushion. At this time,both the upper and lower chambers of the cushion are being loadedsimultaneously. In this portion of the loading, gas from the lowerchamber flows through the flow restriction valve mechanism 112 from thelower chamber to the upper chamber. A rise in pressure now occurs in theupper chamber due to the simultaneous loading by the passenger and theflow of gas from the lower chamber through the directional valverestriction. This rise in pressure is relieved through the main vent(s)in the upper chamber, with gas passing into the vehicle environment.Note that the flow through the restriction valve between the lower andupper chambers in this phase has been tailored by design as previouslydescribed, to proportion the upper and lower chamber pressures tominimize the relative motion of the head and thorax, in order tominimize the neck flexion response.

Thus, in the airbag embodiment just described, the airbag is structuredto enable filling of a first chamber, then a second chamber using gaspassing through the first chamber. When the airbag is loaded bypassenger contact, the loading energy is dissipated by passing gas fromlower chamber back into the upper chamber, and from the upper chamberthrough the vents to the surrounding environment. It has been found thatchambered passenger-side airbags structured as described above are moreefficient with regard to usage of inflation gas than traditional airbagdesigns providing comparable occupant protection. This characteristicenables a relatively lower-output inflator and/or gas source having alower peak pressure and pressure rise rate to be used to inflate theairbag, because the upper chamber is significantly lower in volume thana traditional non-chambered bag of similar coverage. In someapplications (typically an SUV or light truck) it is also possible touse a single stage inflator. In these applications the vehicle may havea favorable pulse, high roof line and large occupant area. Asingle-stage inflator may be employed where dynamic modes for adult ATDscan be met along with the 3 & 6 year old out of position testrequirements as specified in the regulations. In this case the inflatoroutput would be sufficient to properly restrain the unbelted Hybrid III50th percentile male test ATD without being too soft and the smallerunbelted Hybrid III 5th percentile female Anthropomorphic Test Devicewithout being too stiff.

Airbags having the same exterior dimensions and chambered structure maybe used for multiple applications, because variations in airbagperformance characteristics due to design requirements may be achievedby modifying the interior structure of the airbag (for example, bychanging the location of the divider, by modifying the flowcharacteristics of the valve 112 connecting the upper and lowerchambers, by changing the upper chamber vent locations andcharacteristics, and by changing the locations of the seams connectingthe volume control mechanism (VCM) panels to the main and side airbagpanels). This ability to use a common exterior structure provides adegree of uniformity in bag design and manufacturing.

Referring now to FIG. 40, an embodiment 10 of the airbag describedherein may be incorporated into an airbag system 900. Airbag system 900includes at least one gas source 915 (for example, a known inflator orgas generating system) and airbag 10 in accordance with an embodimentdescribed herein. The airbag is operatively coupled to the gas source soas to enable fluid communication therewith upon activation of the gasgenerating system. Airbag system 900 may also include (or be incommunication with) a collision event sensor 910. Collision event sensor910 includes a known collision sensor algorithm that prompts actuationof airbag system 900 via, for example, activation of gas source 915 inthe event of a collision.

Referring again to FIG. 40, airbag system 900 may also be incorporatedinto a broader, more comprehensive vehicle occupant protection system800 including additional elements such as a safety belt assembly 850.FIG. 40 shows a schematic diagram of one exemplary embodiment of such aprotection system. Safety belt assembly 850 includes a safety belthousing 852 and a safety belt 860 extending from housing 852. A safetybelt retractor mechanism 854 (for example, a spring-loaded mechanism)may be coupled to an end portion of the belt. In addition, a knownsafety belt pretensioner 856 may be coupled to belt retractor mechanism854 to actuate the retractor mechanism in the event of a collision.Typical seat belt retractor mechanisms which may be used in conjunctionwith the safety belt embodiments of the present invention are describedin U.S. Pat. Nos. 5,743,480, 5,553,803, 5,667,161, 5,451,008, 4,558,832and 4,597,546, incorporated herein by reference. Illustrative examplesof typical pretensioners with which the safety belt embodiments of thepresent invention may be combined are described in U.S. Pat. Nos.6,505,790 and 6,419,177, incorporated herein by reference.

Safety belt assembly 850 may also include (or be in communication with)a collision event sensor 858 (for example, an inertia sensor or anaccelerometer) including a known collision sensor algorithm that promptsactuation of belt pretensioner 856 via, for example, activation of apyrotechnic igniter (not shown) incorporated into the pretensioner. U.S.Pat. Nos. 6,505,790 and 6,419,177, previously incorporated herein byreference, provide illustrative examples of pretensioners actuated insuch a manner.

As utilized herein, the terms “approximately,” “about,” “substantially”,and similar terms are intended to have a broad meaning in harmony withthe common and accepted usage by those of ordinary skill in the art towhich the subject matter of this disclosure pertains. It should beunderstood by those of skill in the art who review this disclosure thatthese terms are intended to allow a description of certain featuresdescribed and claimed without restricting the scope of these features tothe precise numerical ranges provided. Accordingly, these terms shouldbe interpreted as indicating that insubstantial or inconsequentialmodifications or alterations of the subject matter described and claimedare considered to be within the scope of the invention as recited in theappended claims.

It should be noted that the term “exemplary” as used herein to describevarious embodiments is intended to indicate that such embodiments arepossible examples, representations, and/or illustrations of possibleembodiments and such term is not intended to connote that suchembodiments are necessarily extraordinary or superlative examples.

The terms “coupled,” “connected,” and the like as used herein means thejoining of two members directly or indirectly to one another. Suchjoining may be stationary (e.g., permanent) or moveable (e.g., removableor releasable). Such joining may be achieved with the two members or thetwo members and any additional intermediate members being integrallyformed as a single unitary body with one another or with the two membersor the two members and any additional intermediate members beingattached to one another.

References herein to the positions of elements, for example “top,”“bottom,” “above,” “below,” etc., are merely used to describe theorientation of various elements in the FIGURES. It should be noted thatthe orientation of various elements may differ according to otherexemplary embodiments, and that such variations are intended to beencompassed by the present disclosure.

It is important to note that the construction and arrangement of theairbag as shown in the various exemplary embodiments is illustrativeonly. Although only a few embodiments have been described in detail inthis disclosure, those skilled in the art who review this disclosurewill readily appreciate that many modifications are possible (e.g.,variations in sizes, dimensions, structures, shapes and proportions ofthe various elements, values of parameters, mounting arrangements, useof materials, colors, orientations, etc.) without materially departingfrom the novel teachings and advantages of the subject matter disclosureherein. For example, elements shown as integrally formed may beconstructed of multiple parts or elements, the position of elements maybe reversed or otherwise varied, and the nature or number of discreteelements or positions may be altered or varied. Accordingly, all suchmodifications are intended to be included within the scope of thepresent application. The order or sequence of any process or methodsteps may be varied or re-sequenced according to alternativeembodiments. Other substitutions, modifications, changes and omissionsmay be made in the design, operating conditions and arrangement of theexemplary embodiments.

What is claimed is:
 1. An airbag comprising: at least one panel definingan interior of the airbag; a divider positioned in the interior so as todivide the interior into an upper chamber and a lower chamber; and atleast one tethering mechanism positioned within the lower chamber, theat least one tether mechanism being structured and attached to the atleast one panel so as to restrict movement of a portion of the at leastone panel during airbag inflation such that a first recess is formedalong an exterior surface of the airbag when the airbag is inflated. 2.The airbag of claim 1 wherein the at least one tethering mechanism isattached to the at least one panel such that the recess is structuredand positioned to receive therein a sternum of a vehicle occupantcontacting the airbag after airbag deployment.
 3. The airbag of claim 1wherein the at least one tethering mechanism is structured and attachedto the at least one panel such that at least one lobe is formed adjacentthe recess, the at least one lobe being positioned so as to cushion aportion of the vehicle occupant adjacent the sternum of the vehicleoccupant contacting the airbag after airbag deployment.
 4. The airbag ofclaim 19 further comprising an opening formed in the divider and spacedapart from any edge of the divider, and a flow restriction valvemechanism positioned so as to restrict gas flow through the opening fromthe lower chamber into the upper chamber.
 5. The airbag of claim 1wherein the at least one tethering mechanism has a hollow, generallytubular structure.
 6. The airbag of claim 1 wherein the at least onetethering mechanism is planar and is structured to extend along asubstantially vertical plane when the airbag is inflated.
 7. The airbagof claim 1 wherein the at least one tethering mechanism is structuredand attached to the at least one panel so as to restrict movement of aportion of the at least one panel during airbag inflation such that asecond recess is formed along an exterior surface of the airbag when theairbag is inflated.
 8. The airbag of claim 7 wherein the at least onetethering mechanism is attached to the at least one panel such that thesecond recess is positioned and structured to receive therein a head ofa Hybrid III 6-Year Old collision ATD when the head is positionedresting against or proximate a vehicle instrument panel at a locationspecified as Position-2 for NHTSA collision testing in accordance withFMVSS Standard No.
 208. 9. A vehicle including an airbag in accordancewith claim
 1. 10. An airbag system including an airbag in accordancewith claim
 1. 11. An airbag comprising: at least one panel defining aninterior of the airbag; a divider positioned in the interior so as todivide the interior into an upper chamber and a lower chamber; and atleast one tether positioned within the upper chamber, the at least onetether being attached to the divider and to a portion of the at leastone panel so as to restrict movement of a portion of the divider in adirection toward the lower chamber during inflation of the airbag. 12.The airbag of claim 11 wherein the at least one tether is attached to alocation on the divider which is structured to be an apex or relativelyhighest portion of the divider when the airbag is in an inflatedcondition in a vehicle.
 13. The airbag of claim 11 wherein the at leastone tether is operatively coupled to the divider so as to restrictdeflection of the divider in a direction toward the lower chamber duringairbag inflation, and wherein the at least one tether is operativelycoupled to the at least one panel so as to restrict motion of anexterior surface of the airbag in a direction toward a vehicle occupantduring airbag inflation.
 14. A vehicle including an airbag in accordancewith claim
 11. 15. An airbag system including an airbag in accordancewith claim
 11. 16. An airbag comprising: at least one panel defining aninterior of the airbag; and a divider positioned in the interior so asto divide the interior into an upper chamber and a lower chamber,wherein at least a portion of a leading edge of the divider is notattached to an occupant contact side of the at least one panel.
 17. Theairbag of claim 16 wherein the at least a portion of the leading edgeextends from the divider to form a flap positioned opposite the occupantcontact side and extending into the airbag lower chamber, the flap beingstructured to restrict a flow of gases from the lower chamber into theupper chamber.
 18. The airbag of claim 16 wherein the divider isattached to the at least one panel along at least one attachmentportion, and wherein the divider is unattached to the at least one panelalong at least one non-attachment portion positioned adjacent the atleast one attachment portion, so as to form an associated at least onegas flow passage between the at least one non-attachment portion and theat least one panel.
 19. The airbag of claim 16 wherein at least one gasflow passage is formed between the at least one panel and the divider,wherein the at least a portion of a leading edge of the divider notattached to an occupant contact side of the at least one panel when theairbag is inflated, and wherein the airbag is structured such that theat least one gas flow passage is at least partially closable to restricta flow of gases from the lower chamber to the upper chamber, responsiveto pressure exerted on the occupant contact side by a vehicle occupant.20. A vehicle including an airbag in accordance with claim
 16. 21. Anairbag system including an airbag in accordance with claim 16.